1. Field of the Invention
The present invention relates to cationized hydroxy-alkylcelluloses which are useful as components of shampoos, rinses, treatments, etc. and a process for producing the same.
2. Prior Art
Cationized hydroxyalkylcelluloses are known as components of shampoos, rinses, treatments, etc., since they contain quaternary ammonium groups as substituents. When employed as components of shampoos, rinses, treatments, etc., these cationized hydroxyalkylcelluloses should be highly compatible with surfactants which are employed as the principal components therein.
As a process for the production of cationized hydroxyalkylcelluloses, JP-B 45-20318 has disclosed a process comprising using cellulose as the starting material, adding an etherifying agent and a cationizing agent successively or simultaneously thereto and thus effecting a continuous reaction. However, this process is not advantageous economically, since the etherifying agent and the cationizing agent are each utilized only at a poor efficiency. Moreover, there arises another problem that it is highly troublesome to eliminate the unreacted materials and impurities formed in large amounts as by-products.
Meanwhile, JP-B 59-42681 has disclosed a process with the use of an ethylene oxide derivative or a propylene oxide derivative of cellulose as the starting material. Although a cationizing agent can be utilized at a high efficiency in this process, it is necessary in this process to react and wash again a cellulose ether which has once reacted and washed, i.e., the reaction and washing should be performed twice. In this process, a solvent mixture of isopropanol with water is used as a reaction solvent in most cases. When, however, the obtained product has a high degree of hydroxylalkyl-substitution, it is dissolved in the above reaction solvent. As a result, it becomes difficult to stir the reaction system due to the increased viscosity, which brings about a decrease in the conversion.
Further, in the prior art, there has not been developed so far any process by which the above-mentioned problems can be solved and cationized hydroxyalkylcelluloses having a high compatibility with surfactants can be constantly supplied.